sundial
/ˈsʌndaɪəl/
noun
- An instrument that shows the time of day by the position of a shadow cast by a central pointer (called a gnomon) onto a marked surface.
- The sundial in the park is accurate only when the sun is shining directly on it.
- Before clocks were common, people used a sundial to tell time outdoors.
- The old garden sundial was engraved with the motto 'I count only the sunny hours.'